The BBC's Ben Brown: "The Iraqis are threatening more attacks"

According to US and UK officials, Iraq opened fire in the vicinity of British aircraft. US planes retaliated, firing missiles and laser-guided bombs on an Iraqi missile site before all aircraft returned safely to base.

Baghdad issued a statement confirming it had opened fire on aircraft patrolling the southern no-fly zone.

The statement said a "hostile plane" was "almost certainly shot down".

UK Defence Secretary George Robertson: "We are not going to be intimidated"

It said the planes fired missiles at an Iraqi village killing a farmer and wounding two others.

This was later firmly denied by Major Joe LaMarca, a spokesman for US Central Command in Florida.

Giving details of the incident he said US and British aircraft were conducting a routine patrol at about 0630GMT when the Iraqis fired six to eight surface-to-air missiles from a site southwest of Talil.

Major Joe LaMarca: "We're confident we offered the proper response"

"In response to that unprovoked attack, we responded by firing two Harm missiles and we dropped a number of ... precision-guided munitions at approximately 0715GMT," he said.

The incident is the second clash this week between US and Iraqi forces in the no-fly zones, with Iraq firing on US planes in the north on Monday.

Iraq has made clear it regards the air exclusion zones as part of its own territory and refuses to acknowledge America or the UK's right to patrol them.

A spokesman for the UK's Ministry of Defence also confirmed the latest clashes and added: "The coalition has consistently asserted its determination to police and enforce the no-fly zones over northern and southern Iraq.

The BBC's Caroline Wyatt: "The Iraqi people are fed up with sanctions"

"This firm response to the latest Iraqi provocation is ample evidence of our commitment."

BBC Defence Correspondent Jonathan Marcus says Iraq appears to have embarked upon a calculated policy to challenge the overflights although it is the Iraqis themselves who are likely to come off worse in any protracted struggle.

Earlier Iraq had called on the United Nations Security Council to debate the no-fly zones covering its northern and southern airspace.

The BBC's Jonathan Marcus: "Iraq's air defences may pay heavily for each challenge"

The Iraqi ambassador to the UN, Nizar Hamdoon, said the exclusion zones were illegal and not supported by UN resolutions and again warned Iraq would defend itself if patrols, by UK and US planes, continued.

Sanctions deaths

Iraq has again emphasised the serious cost to the population of eight years of international sanctions.

Iraq blames sanctions for the deaths of thousands of children each month

Iraq's Health Ministry says more than one million children and old people have died since sanctions began.

The mortality rate among children under the age of five had increased 16-fold, it said in a report carried by the Iraqi news agency INA.

In November, 6,369 children under five and 2,584 old people died compared to 258 children and 423 other people in the year before sanctions were imposed.